Blog List

Monday 1 August 2016

Low cycle fatigue tests and damage accumulation models on the rolling shear strength of cross-laminated timber

Published Date
Volume 62, Issue 3, pp 251-262
First online: 

Title 

Low cycle fatigue tests and damage accumulation models on the rolling shear strength of cross-laminated timber

  • Author 
  • Yuan Li 
  • Frank Lam

Abstract

This paper presents a study on rolling shear damage accumulation and duration of load of cross-laminated timber (CLT) with low cycle fatigue tests. The study of the duration-of-load (DOL) effect on strength properties of wood products is typically challenging; it may be more challenging for non-edge-glued CLT considering crosswise layups of wood boards, existing gaps, and non-uniform stress distributions in cross layers. In experimental studies, short-term ramp loading tests and low cycle trapezoidal fatigue loading tests were used to study the DOL behaviour of the CLT rolling shear. The ramp tests were performed to establish the short-term CLT rolling shear strength properties. The low cycle trapezoidal fatigue tests were performed to evaluate the damage accumulation process for the matched specimens under controlled rolling shear stress levels. A stress-based damage accumulation model was further used to investigate the rolling shear DOL effect with model parameters treated as random variables calibrated against one set of the test data. The calibrated model predicted well comparing with the other set of the test data. This verified model provides a robust tool to quantify the DOL effect on rolling shear strength in the core layers of CLT that can be used in future studies of DOL behaviour in CLT under arbitrary loading histories.


References

  1. 1.
    FP Innovations (2011) CLT handbook—Chapter 3 structural design of cross-laminated timber elements. Vancouver, British Columbia
  2. 2.
    Blass HJ, Fellmoser P (2004) Design of solid wood panels with cross layers. Proceedings of the 8th world conference on timber engineering, WCTE 2004, June 14–17, 2004, Lahti, Finland, pp 543–548
  3. 3.
    Aicher S, Dill-Langer G (2000) Basic considerations to rolling shear modulus in wooden boards. Otto-Graf-J 11:157–166
  4. 4.
    Blass HJ, Görlacher R (2003) Brettsperrholz. Berechnungsgrundlagen (in German). Holzbau Kalender, Bruder, Karlsruhe, pp 580–598
  5. 5.
    Fellmoser P, Blass HJ (2004) Influence of RS modulus on strength and stiffness of structural bonded timber elements. CIB-W18/37-6-5, Edinburgh, UK
  6. 6.
    Jöbstl RA, Schickhofer G (2007) Comparative examination of creep of glulam and CLT slabs in bending. CIB-W18/40-12-3, Bled, Slovenia
  7. 7.
    Forest products laboratory (FPL), USDA (2010) Wood handbook—wood as an engineering material (centennial edition). U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, Madison, WI, USA
  8. 8.
    Lam F, Yee H, Barrett JD (1997) Shear strength of Canadian softwood structural lumber. Can J Civil Eng 24(3):419–430CrossRef
  9. 9.
    Li M, Lam F, Li Y (2014) Evaluating rolling shear strength properties of cross laminated timber by torsional shear tests and bending tests. Proceedings of the world conference on timber engineering, WCTE 2014, Quebec City, Canada, August 10–14, 2014
  10. 10.
    EN 1995-1-1 (2004) Eurocode 5: design of timber structures. Part 1–1: general—common rules and rules for buildings. European Committee for Standardization, Brussels
  11. 11.
    Barrett JD, Foschi RO (1978) Duration of load and probability of failure in wood, part 1: modeling creep rupture. Can J Civil Eng 5(4):505–514CrossRef
  12. 12.
    Foschi RO, Barrett JD (1982) Load duration effects in western hemlock lumber. J Struct Div, ASCE 108(7):1494–1510
  13. 13.
    Gerhards CC, Link CL (1987) A cumulative damage model to predict load duration characteristics of lumber. Wood Fiber Sci 19(2):147–164
  14. 14.
    Laufenberg TL, Palka LC, McNatt JD (1999) Creep and creep-rupture behaviour of wood-based structural panels. Project No. 15-65-M404, Forinteck Canada Corp
  15. 15.
    Madsen B (1992) Structural behaviour of timber. Timber Engineering Ltd., Vancouver, British Columbia
  16. 16.
    Bejtka I, Lam F (2008) Cross laminated timber as innovative building material. Proceedings of the Canadian Society for Civil Engineering (CSCE) 2008 annual conference, Quebec City, Canada
  17. 17.
    Li Y (2015) Duration-of-load and size effects on the rolling shear strength of cross laminated timber. Ph.D. Thesis, Department of Wood Science, University of British Columbia
  18. 18.
    Norlin LP (1997) Fatigue behaviour and size effect perpendicular to the grain of laminated Douglas-fir veneer. M. Sc Thesis, Department of Wood Science, University of British Columbia
  19. 19.
    Norlin LP, Norlin CM, Lam F (1999) Shear behaviour of laminated Douglas fir veneer. Wood Sci Technol 33:199–208CrossRef
  20. 20.
    Bodig J, Jayne BA (1982) Mechanics of wood and wood composites. Van Nostrand Reinhold Company, New York
  21. 21.
    Kreuzinger H (1999) Platten, Scheiben und Schalen—ein Berechnungsmodell für gängige Statikprogramme (in German). Bauen Mit Holz 1:34–39
  22. 22.
    Foschi RO (1989) Reliability-based design of wood structures. Structural research series report no. 34, Department of Civil Engineering, University of British Columbia, Vancouver
  23. 23.
    Nielsen LF (1986) Wood as a cracked viscoelastic material. Part I: theory and applications, and part II: sensitivity and justification of a theory. Proceedings of international workshop on duration of load in lumber and wood products, Special Publ. No. SP-27, Forintek Canada Corp., Vancouver, British Columbia, pp 67–89
  24. 24.
    Foschi RO, Yao FZ (1986) Another look at the three duration of load models. Proceedings of IUFRO Wood Engineering Group meeting, Florence, Italy, paper 19-9-1
  25. 25.
    Chen Y (2011) Structural performance of box based cross laminated timber system used in floor applications. Ph.D. Thesis, Department of Forestry, University of British Columbia
  26. 26.
    Yawalata D, Lam F (2011) Development of technology for cross laminated timber building systems. Research report submitted to Forestry Innovation Investment Ltd., University of British Columbia, Vancouver, British Columbia
  27. 27.
    ASTM D198-05a (2005) Standard test method of static tests of lumber in structural sizes. American society for testing and materials (ASTM), USA
  28. 28.
    Barrett JD (1996) Duration of load: the past, present and future. International COST 508 wood mechanics conference. Stuttgart, Germany

For further details log on website :
http://link.springer.com/article/10.1007/s10086-016-1547-6

No comments:

Post a Comment

Advantages and Disadvantages of Fasting for Runners

Author BY   ANDREA CESPEDES  Food is fuel, especially for serious runners who need a lot of energy. It may seem counterintuiti...